Dental dam

ABSTRACT

Premarked dental dams and devices for marking dental dams, are mechanisms that are employed for locating holes to be selectively pierced by the dentist in the dental dam through which teeth protrude. The markings follow the average alignment of teeth as they appear in the dental arch. The patterns of the markings of the teeth of the lower arch are located on the dental dam with respect to the superior edge of the dental dam. One group of patterns represents the primary, mixed and permanent dentition for a 5-inch X 5-inch dental dam. Another group of patterns represents the primary, mixed and permanent dentition for a 6inch X 6-inch dental dam. The pattern of the group selected for a particular arch is dependent on the tooth of that particular arch to be clamped.

United States Patent McConville [4 1 May 16, 1972 [54] DENTAL DAMPrimary ExaminerRobert Peshock 72 Inventor: Richard s. McConville, 2525Bailey Avenue, San Jose, Calif. 95128 57] ABSTRACT [22] Filed: 1971Premarked dental dams and devices for marking dental dams, 2 App] 13 2are mechanisms that are employed for locating holes to be selectivelypierced by the dentist in the dental dam through which teeth protrude.The markings follow the average align- {521 US. Cl ..32/34 ment of teethas they appear in the dental arch. The patterns [51] Int. Cl ..A6lc 5/12of the markings of the teeth of the lower arch are located on [58] Fieldof Search ..32/34; 33/ l the dental dam with respect to the superioredge of the dental dam. One group of patterns represents the primary,mixed and 5 References Cited permanent dentition for a 5-inch X S-inchdental dam. Another group of patterns represents the primary, mixed andUNITED STATES PATENTS permanent dentition for a 6-inch 6-inch dentaldam. The

pattern of the group selected for a particular arch is depen- 278,0915/1883 Burk ..32/34 dent on the tooth ofthat particular arch to beclamped. 1,579,608 4/1926 Haudenshield ..32/34 18 Claims, 5 DrawingFigures J'E T 3 III UPPE R PRlMARY&MlXED l PATENTEUHAY 15 972 3, 662,466

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[11L Rm m E R W WC PMRT R UR L W m ATTORNEY DENTAL DAM BACKGROUND OF THEINVENTION The present invention relates in general to dental devices,and more particularly to a dental dam.

Heretofore, dentists have employed rubber dams to isolate teeth to berestored. Small holes are punched into the apron of the rubber damthrough which teeth protrude. The dam is held securely in the patientsmouth by clamping selected teeth of the dental arch. In using the rubberdam, the teeth isolated by the rubber dam are free from the flow ofsaliva, which would contaminate the restoring material and also whichwould obstruct the view of the dentist.

In order for the rubber dam to function properly, and to fit thepatients face comfortably, the small holes in the rubber dam must belocated so as to follow the alignment of the teeth as they appear in thedental arch. Also, the superior edge of the rubber dam should bepositioned below the nose and the superior portion of the rubber damshould cover the upper lip. The inferior portion of the rubber darnshould be positioned so as to cover all or part of the patients chin.

Heretofore, dentists located various landmarks to serve as guides andmarked the rubber dam through the location of the landmarks. Themarkings were rough estimates for locating holes. Accuracy andconsistency were lacking. Prior efforts to employ templates, guides andrubber stamps in marking or locating markings on rubber dams throughwhich a dentist pierced holes in the dental dam failed to consider therelationship of the superior edge of the rubber darn with respect to thepatterns of the lower dental arch.

Previously existing techniques for locating the holes in the rubber damthrough which teeth protrude were inaccurate and inconsistent, sinceestimating and guess-work were employed. Such techniques were also timeconsuming and did not lend themselves to delegation of duties toassistants and aids by virtue of the complexity thereof.

SUMMARY OF THE INVENTION A device for marking a dental dam which takesinto consideration the relationship of the dental arch to the superioredge of the dental dam.

The premarking of a dental dam which takes into consideration therelationship of the dental arch to the superior edge of the dental dam.

A device for marking a dental dam having a group of patterns for thedental arches taking into consideration different patterns for the lowerdental arch for the primary and mixed dentition, and/or the permanentdentition.

The premarking of a dental dam having a group of patterns for the dentalarches taking into consideration different patterns for the lower dentalarch for the primary and mixed dentition, and/or the permanentdentition.

A device for marking a dental dam having a group of patterns for thedental arches taking into consideration different patterns for the lowerdental arch for the primary and mixed dentition and/or the permanentdentition, which pattern for the dental arch is selected by the tooth tobe clamped.

The premarking of a dental dam having a group of patterns for the dentalarch taking into consideration different patterns for the dental archfor the primary and mixed dentition and/or the permanent dentition,which pattern for the dental arch is selected by the tooth to beclamped.

A dental dam formed with openings to receive teeth, which openings takeinto consideration the relationship of the dental arch to the superioredge of the dental dam.

A dental dam formed with openings to receive teeth, which openings forma group of patterns for the dental arches taking into considerationdifferent patterns for the lower dental arch for the primary and mixeddentition, and/or permanent dentition.

By virtue of the present invention, holes through which teeth are toprotrude in rubber dams can be formed by the producer of the rubber damor by the dentist with greater facility, more accuracy, and in lesstime. Less guess-work and greater consistency are also achieved.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic illustration of aconventional dental dam shown attached to a patients face.

FIG. 2 is a top view of a device embodying the present invention for usein the primary, mixed and permanent dentition for a 5-inch 5-inch dentaldam.

FIG. 3 is a top view of a device embodying the present invention for usein the primary, mixed and permanent dentition for a 6-inch X 6-inchdental dam.

FIG. 4 is a top view of a premarked S-inch 5-inch dental dam embodyingthe present invention for use in the primary, mixed and permanentdentition.

FIG. 5 is a top view of a premarked 6-inch X 6-inch dental dam embodyingthe present invention for use in the primary, mixed and permanentdentition.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Illustrated in FIG. 1 is a thinsheet of flexible elastic material 10, such as sheet rubber, which isplaced over the oral cavity of a patient. Thereupon, a U-shaped frame 11is positioned over the dental dam 10. Patents of general interest inthis regard are the patent to Young, U.S. Pat. No. 682,308, and thepatent to McConville, U.S. Pat. No. 3,406,452.

The dental dam 10 is secured to the frame 11 by turning edges of thedental dam 10, extending outside of the frame 11, over and pressing itagainst the tines of the frame 11. After placing the dental dam 10 onthe frame 11, the frame 11 is strapped to the patients head. Clamps, notshown, position a portion of the dental dam 10 within the oral cavity sothat the dental dam 10 covers a plurality of teeth and adjacent gumarea. One or more holes or openings are provided in the dental dam 10through which teeth protrude to provide access to the desired workingarea that it is to be isolated from oral fluids and other areas toinsure cleanliness of the working area, reduction of contamination ofrestorative material, and reduction of obstruction by fluids to adentist in viewing the working area.

Illustrated in FIG. 2 is a rigid device 15 for a S-inchX 5-inch dentaldam embodying the present invention for use in connection with aprimary, mixed and permanent dentition. The device 15 comprises a rigidbody 15a. At the upper portion of the body 15a is a pattern 16 of holeswhich follow the alignment of teeth as they appear in the average upperdental arch for the primary and mixed dentition. At the lower portion ofthe body 15a are three spaced patterns 17-19 of holes which follow thealignment of teeth as they appear in the average lower dental archrepresenting the primary, mixed and permanent dentition, respectively.In lieu of holes, the device 15 may be formed with patterns ofprojections to produce imprints.

Most frequently, the second primary molar, the first permanent molar andthe second permanent molar are clamped in the primary, mixed andpermanent dentition of the lower arch. When the second primary molar ofthe lower arch is to be clamped, the pattern 17 is used. When the firstpermanent molar of the lower arch is to be clamped, the pattern 18 isemployed and when the second permanent molar of the lower arch is to beclamped, the pattern 19 is used.

The pattern 19 for the clamping of the lower second permanent molar whenthe device 15 is rotated I becomes the pattern of the upper arch for thepermanent dentition.

In FIG. 3 is illustrated a rigid device 20 for a 6-inch X 6-inch dentaldam embodying the present invention for use in connection with aprimary, mixed and permanent dentition. The device 20 comprises a rigidbody 21. At the upper portion of the body 21 is a pattern 22 of holeswhich follow the alignment of teeth as they appear in the average upperdental arch for the primary and mixed dentition. At the lower portion ofthe body 15 are four spaced patterns 24-27. The first three patterns24-26 follow the alignment of teeth as they appear in the average lowerprimary, mixed and permanent dental arch, respectively. The fourthpattern 27 represents the alignment of the average upper dental arch forthe permanent dentition. The device must be rotated 180 to utilize thispattern. Most frequently, the second primary molar, the first permanentmolar and the second permanent molar are clamped in the primary, mixedand permanent dentition of the lower arch. When the second primary molarof the lower arch is to be clamped, the pattern 17 is used. When thefirst permanent molar of the lower arch is to be clamped, the pattern 18is employed and when the second permanent molar of the lower arch is tobe clamped, the pattern 19 is used. In lieu of patterns of holes,

the device 20 may be formed with patterns of projections to produceimprints.

The devices 15 and 20 are used by the dentist to mark the dental dam sothat the dentist can pierce the appropriate markings on the dental damto form holes in the dental dam through which teeth protrude. To do so,a dentist merely places either the device 15 or the device 20, whicheveris appropriate, above a dental dam with the superior edge SE of thetemplate aligned with the superior edge SE of the dental dam. Then, whenthe patterns are of holes, the dentist places a pencil or pen throughthe holes of the patterns appropriate for his purpose and accordinglyimprints markings on the dental dam through which the dentist piercesthe dental dam to form holes through which teeth may protrude. When thepatterns are of projections, ink may be applied to the projections, suchas in using a rubber stamp or any printing device, to produce imprintmarkings on the dental dam.

Illustrated in FIG. 4 is a -inch X 5-inch dental dam 30 incorporatingtherein the present invention. The dental dam 30 comprises a thin sheet31 of suitable plastic, flexible material, which may be rubber. Thedental dam 30 is used in connection with a primary, mixed and. permanentdentition.

At the upper portion of the sheet 31 is a pattern 32 of markings whichfollow the alignment of teeth as they appear in the average upper dentalarch for the primary and mixed dentition. At the lower portion of thesheet 31 are three spaced patterns 33-35, which follow the alignment ofteeth as they appear in the average lower dental arch for the primary,mixed and permanent dentition, respectively.

If one were to place the device (FIG. 2) above the dental dam 30 withthe superior edge .SE of the device 15 coincident with the superior edgeSE ofthe dental dam 30 and then place a suitable writing implement inall of the holes of the patterns 16-19 of holes in the device 15, hewould imprint on the dental dam 30 all the markings shown for thepatterns 32-35 of markings on the dental dam 30.

It is within the contemplation of the present invention to premark thedental dam 30 by a suitable printing apparatus, rubber stamp or the likewith all the markings of the patterns 32-35 of markings shown in FIG. 4for the rubber dam 30. This will, of course, obviate the need of thedevice 15. Further it is within the contemplation of the presentinvention to have a dental dam in which openings are preformed in thedental dam in lieu of premarking the dental dam in the manner aforesaid.In this regard one or more groups of patterns can be formed by openingsin lieu of marks'at the locations previously described for marks.

It is apparent, of course, that the selection of the patterns 33-34 ofmarkings of the lower arch of the dental dam 30 is made in accordancewith the teeth of the lower dental arch to be clamped. The disclosurepreviously made in connection with the selection of patterns 17-19 forthe device 15 is equally applicable to the selection of patterns 33-35of markings for the dental dam 30.

In FIG. 5 is a 6-inch X 6-inch dental dam 40 incorporating therein thepresent invention. The dental dam 40 comprises a thin sheet 41 ofsuitable plastic flexible material, which may be rubber. The dental dam40 is used in connection with the I primary, mixed and permanentdentition.

At the upper portion of the sheet 41 is a pattern 42 of markings whichfollow the alignment of teeth as they appear in the average upper dentalarch for the primary and mixed dentition. At the lower portion of thesheet 41 are four spaced patterns 43-46. The patterns 43-45 follow thealignment of the teeth as they appear in the average lower primary,mixed and permanent dental arch, respectively. Pattern 46 represents theaverage dental arch of the upper permanent dentition. The dam must berotated 180 to utilize this pattern properly.

If one were to place the device 20 (FIG. 3) above the dental dam withthe superior edge SE of the device 20 aligned with the superior edge SEof the dental dam 40 and then place a suitable writing implement in allof the holes of the device 20, he would imprint on the dental dam 40 allthe markings shown for the patterns 42-46 of markings on the dental dam40.

It is within the contemplation of the present invention to premark thedental dam 40 by a suitable printing apparatus, rubber stamp or thelike, all the markings of the patterns 42-46 of markings shown in FIG. 5for the rubber dam 40. This will, of course, obviate the need of thedevice 20. Further, it is within the contemplation of the presentinvention to have a dental dam in which openings are preformed in thedental dam in lieu of premarking the dental dam in the manner aforesaid.In this regard one or more groups of patterns can be formed by openingsin lieu of marks at the locations previously described for marks. It isapparent, of course, that the selection of the patterns 43-45 ofmarkings or openings of the lower arch of the dental dam 40 is made inaccordance with the teeth of the lower arch to be clamped. Thedisclosure previously made in connection with the selection of patterns24-27 of markings is equally applicable to the selection of patterns43-46 of markings for the rubber dam 40 or that matter preformed holesfor the rubber dam 40.

The holes to be pierced in the dental dam for receiving the uppercentral incisors should be approximately 1 inch from the superior edgeSE of the dental dam. Thus, the forwardmost hole or projection of thepatterns 16 and 22 should be approximately I inch from the superior edgeSE of the devices 15 and 20. Similarly, the forwardmost marking of thepatterns 32 and 42 of markings of the dental dams 30 and 40 should beapproximately one inch from the superior edge SE of the dental dams 30and 40.

The holes to be punched in the dental dam for the permanent dental archshould be approximately 6 millimeters apart and the holes to be punchedin the dental dam for the primary and mixed arch should be approximately5 millirneters apart. The patterns 16-19, 22, 24-27, 32-35 and 42-46follow average arch curvature and distances between teeth.

It has been found that when the upper second molar is to be clamped, thehole formed in the dental dam to receive the upper first permanent molarshould be about 1 inch superior to the hole to be pierced in the rubberdam to receive the lower first permanent molar (See FIGS. 2 and 4).Thus, the holes in the device 15 and the markings in the rubber dam 30are found to achieve this end.

From the foregoing, it is to be observed that there is a directrelationship between the superior edge SE of a dental dam and thelocation of the hole to be pierced for receiving a tooth in the lowerarch to be clamped. The superior edge SE of the dental dam, aspreviously disclosed, is the edge of the dental dam below the nose ofthe patient and above the upper lip of the patient. Thus, the moredistal the tooth to be clamped in the lower arch, the lower the patternof the lower arch must be on the dental dam. (See patterns 33-35 of thedental dam 30 and patterns 43-46 of the dental dam 40.) It is apparentthat the further into the distal portion of the oral cavity the dentaldam must be attached, the more material of the dental dam is required tocover the upper lip. Therefore, if a pattern for locating holes to bepierced by a dentist or the holes preformed by the producer of therubber dam for receiving teeth is to be located with reasonableaccuracy, the pattern of a given lower arch must be designated theproper distance from the superior edge SE of the dental dam. However,the relationship of the tooth clamped in the upper arch and the superioredge SE of the dental dam is relatively constant and has only slightvariations.

I claim: 1. A device for locating a marking on a dental dam whichmarking is pierced to form a hole through which hole a tooth protrudescomprising:

a rigid body with a superior edge; means on said body defining a firstpattern for a lower dental arch, pattern is spaced a predetermineddistance from the superior edge of said body and follows the alignmentof teeth as they appear in the lower dental arch; and

means on said body defining at least one second pattern for a lowerdental arch, said second patterns being spaced apart from said firstpattern in a direction perpendicular to said superior edge, each of saidsecond patterns being spaced a predetermined distance from the superioredge of said body and follows the alignment of teeth as they appear inthe lower dental arch.

2. A device as claimed in claim 1 and comprising means on said bodydefining a second pattern for an upper dental arch,

which second pattern is spaced a predetermined distance from thesuperior edge of said body and follows the alignment of teeth as theyappear in the upper dental arch.

3. A device as claimed in claim 2 and comprising means on said bodydefining a third pattern of holes for an upper dental arch, which thirdpattern of holes is spaced a predetermined distance from the superioredge of said body and follows the alignment of teeth as they appear inthe upper dental arch.

4. A device as claimed in claim 1 wherein one of said second patterns ofsaid lower dental arch follows the alignment of teeth as they appear inthe upper dental arch in response to said rigid body being rotated 180.

5. A device as claimed in claim 1 wherein said first pattern is formedby openings.

6. A device as claimed in claim 1 wherein said first pattern is formedby projections.

7. A device as claimed in claim 3 wherein said first, second and thirdpatterns are formed by openings.

8. A device as claimed in claim 3 wherein said first, second and thirdpatterns are formed by projections.

9. A dental dam in which a hole is pierced and through which hole atooth protrudes comprising:

a flexible sheet with a superior edge;

markings on said sheet defining a first pattern of markings for a lowerarch which pattern of markings is spaced a predetermined distance fromthe superior edge of said sheet and follows the alignment of teeth asthey appear in the lower dental arch; and

markings on said sheet defining at least one second pattern of markingsfor a lower dental arch, said second patterns of markings being spacedapart from said first pattern of markings in a direction perpendicularto said superior edge, each of said second patterns of markings beingspaced a predetermined distance from the superior edge of said sheet andfollows the alignment of teeth as they appear in the lower dental arch.

10. A dental dam as claimed in claim 9 and comprising markings on saidsheet defining a second pattern of markings for an upper dental arch,which second pattern of markings is spaced a predetermined distance fromthe superior edge of said sheet and follows the alignment of teeth asthey appear in the upper arch.

11. A dental dam as claimed in claim 10 and comprising markings on saidsheet defining a third pattern of markings for an upper dental arch,which third pattern of markings is spaced a predetermined distance fromthe superior edge of said sheet and follows the alignment of teeth asthey appear in the upper dental arch.

12. A dental dam as claimed in claim 9 wherein said markings are formedsimultaneously on said sheet.

13. dental dam as claimed in claim 11 wherein said markings are formedsimultaneously on said sheet.

14. A dental dam as claimed in claim 9 wherein one of said secondpatterns of said lower dental arch follows the alignment of teeth asthey appear in the upper dental arch in response to said flexible sheetbeing rotated 15. A dental dam comprising:

a flexible sheet with a superior edge;

holes on said sheet forming a first pattern for a lower arch whichpattern is spaced a predetermined distance from the superior edge ofsaid sheet and follows the alignment of teeth as they appear in thelower dental arch; and

holes on said sheet forming at least one second pattern for a lowerdental arch, said second patterns being spaced from said first patternin a direction perpendicular to said superior edge, each of said secondpatterns being spaced a predetermined distance from the superior edge ofsaid sheet and follows the alignment of teeth as they appear in thelower dental arch.

16. A dental dam as claimed in claim 15 and comprising holes on saidsheet forming a second pattern for an upper dental arch, which secondpattern is spaced a predetermined distance from the superior edge ofsaid sheet and follows the alignment of teeth as they appear in theupper arch.

17. A dental dam as claimed in claim 16 and comprising holes on saidsheet forming a third pattern for an upper dental arch, which thirdpattern is spaced a predetermined distance from the superior edge ofsaid sheet and follows the alignment of teeth as they appear in theupper dental arch.

18. A dental dam as claimed in claim 15 wherein one of said secondpatterns of said lower dental arch follows the alignment of teeth asthey appear in the upper dental arch in response to said flexible sheetbeing rotated 180.

1. A device for locating a marking on a dental dam which marking ispierced to form a hole through which hole a tooth protrudes comprising:a rigid body with a superior edge; means on said body defining a firstpattern for a lower dental arch, pattern is spaced a predetermineddistance from the superior edge of said body and follows the alignmentof teeth as they appear in the lower dental arch; and means on said bodydefining at least one second pattern for a lower dental arch, saidsecond patterns being spaced apart from said first pattern in adirection perpendicular to said superior edge, each of said secondpatterns being spaced a predetermined distance from the superior edge ofsaid body and follows the alignment of teeth as they appear in the lowerdental arch.
 2. A device as claimed in claim 1 and comprising means onsaid body defining a second pattern for an upper dental arch, whichsecond pattern is spaced a predetermined distance from the superior edgeof said body and follows the alignment of teeth as they appear in theupper dental arch.
 3. A device as claimed in claim 2 and comprisingmeans on said body defining a third pattern of holes for an upper dentalarch, which third pattern of holes is spaced a predetermined distancefrom the superior edge of said body and follows the alignment of teethas they appear in the upper dental arch.
 4. A device as claimed in claim1 wherein one of said second patterns of said lower dental arch followsthe alignment of teeth as they appear in the upper dental arch inresponse to said rigid body being rotated 180*.
 5. A device as claimedin claim 1 wherein said first pattern is formed by openings.
 6. A deviceas claimed in claim 1 wherein said first pattern is formed byprojections.
 7. A device as claimed in claim 3 wherein said first,second and third patterns are formed by openings.
 8. A device as claimedin claim 3 wherein said first, second and third patterns are formed byprojectiOns.
 9. A dental dam in which a hole is pierced and throughwhich hole a tooth protrudes comprising: a flexible sheet with asuperior edge; markings on said sheet defining a first pattern ofmarkings for a lower arch which pattern of markings is spaced apredetermined distance from the superior edge of said sheet and followsthe alignment of teeth as they appear in the lower dental arch; andmarkings on said sheet defining at least one second pattern of markingsfor a lower dental arch, said second patterns of markings being spacedapart from said first pattern of markings in a direction perpendicularto said superior edge, each of said second patterns of markings beingspaced a predetermined distance from the superior edge of said sheet andfollows the alignment of teeth as they appear in the lower dental arch.10. A dental dam as claimed in claim 9 and comprising markings on saidsheet defining a second pattern of markings for an upper dental arch,which second pattern of markings is spaced a predetermined distance fromthe superior edge of said sheet and follows the alignment of teeth asthey appear in the upper arch.
 11. A dental dam as claimed in claim 10and comprising markings on said sheet defining a third pattern ofmarkings for an upper dental arch, which third pattern of markings isspaced a predetermined distance from the superior edge of said sheet andfollows the alignment of teeth as they appear in the upper dental arch.12. A dental dam as claimed in claim 9 wherein said markings are formedsimultaneously on said sheet.
 13. A dental dam as claimed in claim 11wherein said markings are formed simultaneously on said sheet.
 14. Adental dam as claimed in claim 9 wherein one of said second patterns ofsaid lower dental arch follows the alignment of teeth as they appear inthe upper dental arch in response to said flexible sheet being rotated180*.
 15. A dental dam comprising: a flexible sheet with a superioredge; holes on said sheet forming a first pattern for a lower arch whichpattern is spaced a predetermined distance from the superior edge ofsaid sheet and follows the alignment of teeth as they appear in thelower dental arch; and holes on said sheet forming at least one secondpattern for a lower dental arch, said second patterns being spaced fromsaid first pattern in a direction perpendicular to said superior edge,each of said second patterns being spaced a predetermined distance fromthe superior edge of said sheet and follows the alignment of teeth asthey appear in the lower dental arch.
 16. A dental dam as claimed inclaim 15 and comprising holes on said sheet forming a second pattern foran upper dental arch, which second pattern is spaced a predetermineddistance from the superior edge of said sheet and follows the alignmentof teeth as they appear in the upper arch.
 17. A dental dam as claimedin claim 16 and comprising holes on said sheet forming a third patternfor an upper dental arch, which third pattern is spaced a predetermineddistance from the superior edge of said sheet and follows the alignmentof teeth as they appear in the upper dental arch.
 18. A dental dam asclaimed in claim 15 wherein one of said second patterns of said lowerdental arch follows the alignment of teeth as they appear in the upperdental arch in response to said flexible sheet being rotated 180*.